Printed circuit boards are used in electronic equipment, e.g., computers. In such boards, copper wiring or the like having a predetermined pattern is formed on one or both surfaces of an insulating base.
A printed circuit board of that sort is made in the following process steps. A laminate, consisting of a photosensitive resin layer (photoresist) and a translucent resin film (protective film) for protecting the photosensitive resin layer, is bonded onto a conductive layer provided on an insulating base through thermocompression bonding. The thermocompression bonding of laminates is conducted by a laminator on a mass-production basis. Then a wiring pattern mask is superposed on the laminate, and the photosensitive resin layer is exposed to light for a predetermined period of time thorough the wiring pattern mask and the translucent resin film. The photosensitive resin layer thus exposed to light is developed to form an etching mask pattern after the translucent resin film is peeled off by a peeling device. Unnecessary portions of the conductive layer are subsequently removed by etching and the remaining photosensitive resin layer is also removed to form a printed circuit board having a predetermined wiring pattern.
During the above process of manufacturing the printed circuit board, there is required the step of forming the laminate consisting of the photosensitive resin layer and the translucent resin film and bonding the laminate onto the insulating base. A roll of laminate continuously wound on a supply roll of a film laminator is pulled out and then cut into pieces corresponding in dimensions of the base to provide a laminate to be bonded thereto.
An apparatus for conveying the base to the thermocompression roller position is equipped with solid or hollow barlike conveyor rollers and pressure rollers. The base is held between the barlike conveyor rollers and the presser rollers and is conveyed as the rollers rotate. When the base is moved close to the thermocompression rollers, the base is slid by fixed crosswise guide members in a direction perpendicular to the conveyance direction (the width direction thereof) for registering it before being nipped between the thermocompression rollers.
When a base which readily tends to warp is conveyed, however, such crosswise guide members are incapable of accurately setting the center line or one end of the base to the center line or other predetermined position in the conveyance direction of the base conveying apparatus.
Because of the above problem, there may be installed a crosswise base sliding device (path deflector) for making the center line in the conveyance direction of the base or one end thereof coincide with the center line in the conveyance direction of the apparatus or the predetermined position. The front end of the base is detected with a base position detecting sensor to let the crosswise base sliding device start operation according to the detection signal, whereas the width of the base is detected with base width detecting sensors to let the crosswise base sliding device stop operation.
If the base is extremely thin, when the base is slid crosswise with the crosswise base sliding members and if the conveyor rollers and the presser rollers are joined to each other, however, the base, forced to move in the direction perpendicular to the conveyance direction with the crosswise base sliding members, will be pressed hard by the conveyor rollers and the presser rollers and not be readily movable because of frictional resistance between each roller and the base. Since the base is pressed hard with the crosswise base sliding members, the base portion thus pressed hard will bend and the problem is that the base cannot surely be slid in the direction perpendicular to the conveyance direction.
The presser rollers may be dispensed with to solve the above problem but, when the base is pressed with the sliding members without using the presser rollers, the base will yield to the pressure and will also bend. Consequently, the base cannot be slid crosswise.
The above-described and other problems to be solved by the present invention and novel features thereof will become manifest upon making reference to the detailed description which follows and the accompanying drawings.